It could be strong since abilities are pretty unique, take +Life/Dmg or the new +Pillz/Dmg. SoA & SoB are also powerful abilities.

The reason why it's strong is because you hardly see players use cards with mediocre abilities (E.g. Lily, Embolt, etc.) so usually abilities you go against are powerful ones, with the exception of certain cards like Kerozinn Cr. Heck, if you go against Crassus chances are you have a 1HKO in store for the opponent.

Of course it's not impossible, but perhaps such cards will have mediocre stats, such as, 3* 7/3 CoA in Skeelz and maybe 3* 5/4 in clans like Bangers or Rescue.

Yes, because it would be hard to normalize a card around so many different abilities in the game. Give them too much damage and copying Kenny's ability would make it too powerful. Have too much power and you can easily turn the game around with an ability like -4 opp power, min 4.

It's not that it is totally impossible to make a card that satisfies all conditions, but it would be too much of a wildcard and would be either extremely weak or extremely powerful.

That probably would not work. But if they would do this the abilities should be something like Backslash: Opp: +2 pillz, +2life. But everything would become broken.
1. Scenario: People would start using cards without abilities or Sob everywhere
2. Scenario. Nobody would use clan with ability: Opp. Ability

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